3.2Mt/a歧化及烷基转移装置运行状况分析

OPERATIONAL STATUS ANALYSIS OF 3.2MT/A DISPROPORTIONATION AND TRANSALKYLATION UNIT

介绍了某公司歧化及烷基转移装置反应器压力降上升快,混合芳烃总转化率偏低、氢耗偏高等问题.为保证装置平稳运行提出了操作建议,但该建议仍无法阻止反应器操作压力降的持续上升,6个月后被迫停工检修.发现反应器入口扩散器严重损坏,催化剂床层被严重搅乱,催化剂粉化严重并结焦;为此,修复了反应器入口扩散器,反应器顶部催化剂被卸出、过筛、回装并补充部分新鲜催化剂.重新投运后,装置操作参数仍不理想,于2018年8月更换催化剂,换剂后混合芳烃总转化率、苯和C8芳烃的总选择性、氢耗等均达到或优于设计值.

This paper introduces the problems of high pressure drop, low total conversion of mixed aromatics and high hydrogen consumption in the reactor of disproportionation and transalkylation unit of a company. Although some operational suggestions were put forward to maintain the operation of the unit, the operating pressure of the reactor continued to rise, and the reactor was forced to shut down for maintenance after about 6 months. It was found that the diffuser at the reactor inlet was seriously damaged, the catalyst bed was seriously disturbed, and the catalysts were powdered and coked. The diffuser at the reactor inlet was repaired, the catalysts at the top of the reactor were discharged, screened and refilled, and some fresh catalysts were added. After the unit was restarted up, the operation parameters were still unsatisfactory, and the catalysts were replaced in August 2018. Then the total conversion of mixed aromatics, the total selectivity of benzene and C8 aromatics and the hydrogen consumption reached or surpassed the design value.